The invention relates to an automatically executed shift in a vehicle variable transmission.
Automatic or automated transmission of vehicles usually engage in accordance with preset shift programs which allow different parameters of the existing state of the vehicle and driver""s requests to enter into the calculation of a suitable reduction ratio of the transmission. The sensors that produce the different parameters cannot detect imminent driving situations and influences upon the vehicle originating form the traffic situation and thus also cannot be the basis of a calculation. Situations can thus occur in which the transmission does shift but that are unsuitable and disagreeable for the driver. In those cases the transmission can shift at a moment unforeseeable for the driver or also an unforeseeably higher gear change not suited to the existing traffic situation or topography can be carried out.
EPO 0 170 465 B1 has disclosed by way of example for automated transmissions that calculating shift programs of the transmission indicate to the driver the gear engaged and possible ratio steps which the driver could engage in the vehicle parameters existing at the time both for upshifts and downshifts. Which gear to choose remains left to the driver. In this case the same as formerly, the driver himself has to execute the shifting operation.
The problem on which the invention is based is, in an automatic or automated transmission, to assist a change of the reduction ratio in the transmission which is related to the driving situation.
The proplem is solved by the characteristic features of claim 1. Developments are object of sub-claims.
In a device for shifting an automatic or automated variable transmission of a vehicle with a transmission control and a display device for the driver, the display device is provided in order to give the driver advanced notice of the imminent gear shift. Thereby the driver can correctly control the vehicle according to the traffic situation or also to topography. In a preferred embodiment the display device is designed acoustically, optically or mechanically. One embodiment shows designing the display device so that it indicates the number of gear steps when changing the reduction ratio. In another development is provided a device with which the driver, after advanced notice of the gear shift, can execute in the transmission control a correction engagement. In another advantageous development a device is provided with which the driver, after advanced notice of the gear shift, can prevent the gear shift.
By the driver being prepared for the gear shift as this is to be attained by the display device, the driver acquires a subjectively better feeling relative to the gear shift course. He can adjust to the eventually generating interruption of the traction. An imminent traffice situation such as a traffic light signal installation blocking the thoroughfare, the end of a bottleneck, a level crossing or pedestrian crossing is detected by the driver with his sense organs. The same applies to the detection of an imminent gradient after a long drive on flat road or reaching of the bottom of the valley after long uphill drive possibly using additional braking devices of the vehicle. The imminent situation can likewise require a shift over several gear steps or conversely not allow it or make it seem unsuitable. The driver can decide whether an advanced notice of a shift still is or is not adequate. He will allow it, correct it, or prevent it accordingly.